Calamus (Acorus Calamus) is common in Europe, the Baltic states, the Caucasus, Asia Minor, India, China, Japan, and North America. Acorus Calamus is a perennial herb, 60-100 cm high. The rhizome is thick, cylindrical, sinuous, covered in a spiral top with dark wide leaf scars, located horizontally, almost on the surface. Calamus roots are thin, fibrous, located in nodes. The stem is up-straight, unbranched. The leaves are xiphoid. The flowers are small, green-yellow, bisexual. The plant blooms in May and July. The fruit is a leathery multi-seeded red berry.